From a0c2dc1fe63e2869b74c1c7f6a81d1745c8a695d Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 4 Oct 2019 11:08:34 -0700 Subject: [PATCH] nfc: fix memory leak in llcp_sock_bind() sysbot reported a memory leak after a bind() has failed. While we are at it, abort the operation if kmemdup() has failed. BUG: memory leak unreferenced object 0xffff888105d83ec0 (size 32): comm "syz-executor067", pid 7207, jiffies 4294956228 (age 19.430s) hex dump (first 32 bytes): 00 69 6c 65 20 72 65 61 64 00 6e 65 74 3a 5b 34 .ile read.net:[4 30 32 36 35 33 33 30 39 37 5d 00 00 00 00 00 00 026533097]...... backtrace: [<0000000036bac473>] kmemleak_alloc_recursive /./include/linux/kmemleak.h:43 [inline] [<0000000036bac473>] slab_post_alloc_hook /mm/slab.h:522 [inline] [<0000000036bac473>] slab_alloc /mm/slab.c:3319 [inline] [<0000000036bac473>] __do_kmalloc /mm/slab.c:3653 [inline] [<0000000036bac473>] __kmalloc_track_caller+0x169/0x2d0 /mm/slab.c:3670 [<000000000cd39d07>] kmemdup+0x27/0x60 /mm/util.c:120 [<000000008e57e5fc>] kmemdup /./include/linux/string.h:432 [inline] [<000000008e57e5fc>] llcp_sock_bind+0x1b3/0x230 /net/nfc/llcp_sock.c:107 [<000000009cb0b5d3>] __sys_bind+0x11c/0x140 /net/socket.c:1647 [<00000000492c3bbc>] __do_sys_bind /net/socket.c:1658 [inline] [<00000000492c3bbc>] __se_sys_bind /net/socket.c:1656 [inline] [<00000000492c3bbc>] __x64_sys_bind+0x1e/0x30 /net/socket.c:1656 [<0000000008704b2a>] do_syscall_64+0x76/0x1a0 /arch/x86/entry/common.c:296 [<000000009f4c57a4>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 30cc4587659e ("NFC: Move LLCP code to the NFC top level diirectory") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller --- net/nfc/llcp_sock.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/net/nfc/llcp_sock.c b/net/nfc/llcp_sock.c index 8dfea26536c9..ccdd790e163a 100644 --- a/net/nfc/llcp_sock.c +++ b/net/nfc/llcp_sock.c @@ -107,9 +107,14 @@ static int llcp_sock_bind(struct socket *sock, struct sockaddr *addr, int alen) llcp_sock->service_name = kmemdup(llcp_addr.service_name, llcp_sock->service_name_len, GFP_KERNEL); - + if (!llcp_sock->service_name) { + ret = -ENOMEM; + goto put_dev; + } llcp_sock->ssap = nfc_llcp_get_sdp_ssap(local, llcp_sock); if (llcp_sock->ssap == LLCP_SAP_MAX) { + kfree(llcp_sock->service_name); + llcp_sock->service_name = NULL; ret = -EADDRINUSE; goto put_dev; }